Rodent models of the motoric side-effects of neuroleptic drugs, drug-induced Parkinsonism and Tardive Dyskinesia are only partially consistent with the human syndrome. Additionally, the coexistence of the two syndromes is not predicted by current interpretations of the basis of the disorders. Recent evidence suggests that the two are expressed by way of separable striatal efferent "channels" which are dissociable by both pharmacological (dopamine receptor subtypes) and anatomical grounds. We propose here to examine the behavioral pharmacological characteristics of the two major striatal efferent systems. This will be done by examining the behavioral effects of D-1 and D-2 selective agonists and antagonists following electrolytic lesions of the striato-nigral pathway or kainic acid-induced lesions of the entopeduncular nucleus. Catalepsy, stereotypic behavior and rotational models will be used.